US9964577B2 - Wireless terminal testing system - Google Patents
Wireless terminal testing system Download PDFInfo
- Publication number
- US9964577B2 US9964577B2 US15/565,305 US201615565305A US9964577B2 US 9964577 B2 US9964577 B2 US 9964577B2 US 201615565305 A US201615565305 A US 201615565305A US 9964577 B2 US9964577 B2 US 9964577B2
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- device under
- under test
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0807—Measuring electromagnetic field characteristics characterised by the application
- G01R29/0814—Field measurements related to measuring influence on or from apparatus, components or humans, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning
- G01R29/0821—Field measurements related to measuring influence on or from apparatus, components or humans, e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning rooms and test sites therefor, e.g. anechoic chambers, open field sites or TEM cells
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/10—Radiation diagrams of antennas
- G01R29/105—Radiation diagrams of antennas using anechoic chambers; Chambers or open field sites used therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/10—Radiation diagrams of antennas
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/20—Monitoring; Testing of receivers
- H04B17/29—Performance testing
Definitions
- the present disclosure relates to the field of testing technology, and more particularly, to a system for testing a wireless terminal.
- radiated performance test of a wireless terminal radiation signals and receiver sensitivities in a plurality of directions should be measured, and a total radiated power (TRP for short) and a total isotropic sensitivity (TIS for short) are obtained by mathematical calculation based on the measured data.
- TRP total radiated power
- TIS total isotropic sensitivity
- a mobile terminal under test is put on a center of a three dimensional turntable, and may rotate around two axes with the turntable.
- the direct signal emitted to the test antenna by the mobile terminal under test is received by the test antenna, and the radiation signals emitted to other directions by the mobile terminal are absorbed by absorbing material set in the anechoic chamber.
- the mobile terminal is rotated with a preset angle interval according to a test demand.
- the mobile terminal is stopped to measure the signal strength when rotated to each position.
- a test duration may be reduced by adjusting the angle interval.
- test speed of this system is low, and it is needed that a distance between the test antenna and the device under test to be larger than a far field distance, thus causing a huge volume, a high manufacturing cost, and a small application scope of the test system.
- the wireless terminal is configured as a device under test.
- the system includes: a test antenna; a reflecting surface, configured to totally reflect one or more first wireless signals emitted by the device under test; and an absorbing screen, configured to absorb one or more second wireless signals emitted by the device under test, in which the one or more second wireless signals are emitted by the device under test toward a direction of the test antenna without reflection through the reflecting surface; a controller, coupled to the device under test and configured to control the device under test to emit the one or more first and second wireless signals; a power detection device, configured to detect a power of the one or more first wireless signals reflected by the reflecting surface and received by the test antenna; in which the device under test, the test antenna and the reflecting surface correspond to a same ellipsoid, the device under test and the test antenna are arranged at two foci of the ellipsoid respectively, the reflecting surface is arranged on the ellipsoidal surface, and the
- FIG. 1 is a schematic diagram illustrating a structure of a system for testing a wireless terminal according to embodiments of the present disclosure
- FIG. 2 is a schematic diagram illustrating a signal reflection principle of a system for testing a wireless terminal according to embodiments of the present disclosure
- FIG. 3 is a schematic diagram illustrating a space coordinate system of a system for testing a wireless terminal according to embodiments of the present disclosure
- FIG. 4 is a schematic diagram illustrating a structure of a conventional system for testing a wireless terminal
- FIG. 5 is a schematic diagram illustrating a structure of a system for testing a wireless terminal according to another embodiment of the present disclosure
- FIG. 6 is a schematic diagram illustrating a system for testing a wireless terminal and with three reflecting surfaces according to embodiments of the present disclosure
- FIG. 7 is a schematic diagram illustrating a system for testing a wireless terminal and with six reflecting surfaces according to embodiments of the present disclosure
- FIG. 8 is a schematic diagram illustrating a system for testing a wireless terminal and with an annular reflecting surface according to embodiments of the present disclosure
- FIG. 9 is a schematic diagram illustrating a system for testing a wireless terminal and with a spherical reflecting surface according to embodiments of the present disclosure.
- FIG. 1 is a schematic diagram illustrating a structure of a system for testing a wireless terminal according to an embodiment of the present disclosure.
- the system for testing a wireless terminal includes a device under test 10 , a test antenna 20 , a reflecting surface 30 , an absorbing screen 40 , a controller 50 and a power detection device 60 .
- the device under test 10 may be a wireless terminal; the reflecting surface 30 is configured to totally reflect one or more wireless signals emitted by the device under test 10 ; and the device under test 10 , the test antenna 20 and the reflecting surface 30 correspond to a same ellipsoid, in which the device under test 10 and the test antenna 20 are arranged at two foci of the ellipsoid respectively, and the reflecting surface 30 is arranged on the ellipsoidal surface; and the absorbing screen 40 is arranged on a straight line between the device under test 10 and the test antenna 20 .
- the ellipsoid may be a virtual ellipsoid or a physical ellipsoid made of a nonmetallic material, for example a thin wall made of plastic.
- the reflecting surface 30 is made of a metallic material such copper or aluminum.
- the reflecting surface 30 is arranged at a position of the ellipsoidal surface and is consistent with the ellipsoidal surface at where the reflecting surface 30 is arranged, i.e. the reflecting surface 30 becomes a part of the virtual ellipsoidal surface.
- the reflecting surface 30 may be obtained by metallization at a preset position on an inside wall of a plastic ellipsoidal surface.
- the shape of the reflecting surface 30 may include a plurality of types such as an annular type, bar-type etc., which will not be listed one by one.
- the absorbing screen 40 is made of wave-absorbing material which can absorb a radio wave, such as an electromagnetic wave.
- the absorbing screen 40 is configured to absorb a direct signal emitted from the device under test 10 to the test antenna 20 .
- the controller 50 is coupled to the device under test 10 and configured to control the device under test 10 to emit the one or more wireless signals.
- the power detection device 60 is configured to detect a power of one or more wireless signals received by the test antenna 20 .
- an electromagnetic wave signal emitted from one focus may be reflected to the other focus by the reflecting surface 30 .
- propagation path lengths L 1 , L 2 and L 3 of electromagnetic wave signals that are emitted from one focus and reflected by the reflecting surface 30 to the other focus are the same. Therefore, phase differences caused by the propagation paths are same, thus when the electromagnetic wave signals emitted from one focus are reflected and converged to the other focus, in-phase superposition may be achieved.
- the absorb screen 40 is specifically arranged between the device under test 10 and the test antenna 20 to absorb the direct signal emitted from the device under test 10 to the test antenna 20 without reflection.
- the propagation path of the direct signal is different from that of the reflected signal and the phase differences caused by the different propagation paths may be different too. If the direct signal emitted from the device under test to the test antenna 20 is not absorbed or blocked, objectives such as in-phase superposition and power combining may not be achieved when the direct signal and the reflected signal arrive at the test antenna 20 . Since the direct signal is absorbed by the absorbing screen 40 , the influence of the direct signal is no longer considered in following descriptions.
- the number and position(s) of the reflecting surface(s) 30 may be selected according to the test demand of the device under test 10 .
- a coordinate system as illustrated in FIG. 3 is utilized, and a mobile phone is taken as an example of the device under test 10 .
- a direction of a longest side of the mobile phone is taken as a z axis, a top side of the mobile phone is toward a positive direction of the z axis; an x axis is perpendicular to a screen of the mobile phone, and a positive direction of the x axis points to a front side of the screen.
- the signals are emitted by the mobile phone under a control of the controller 50 .
- the direct signal emitted by the device under test 10 in the direction towards the test antenna 20 cannot be measured because it is absorbed by the absorbing screen 40 . Therefore, when the wireless signal in that direction needs to be measured, the device under test 10 should be rotated, so that the wireless signal in that direction may be reflected to the test antenna 20 by the reflecting surface 30 arranged in a corresponding position. Then a radiated power in that direction and the power sum of a plurality of directions of the device under test 10 may be obtained by changing the number of the reflection surfaces 30 or by a data processing method, etc.
- the system for testing a wireless terminal may further include an anechoic chamber 70 .
- the anechoic chamber 70 includes a shielding box 71 and wave-absorbing material 72 .
- the anechoic chamber 70 includes the shielding box 71 and the wave-absorbing material 72 laid inside the shielding box 71 .
- the shielding box 71 is made of a metallic material and configured to shield electromagnetic interference of outside.
- the wave-absorbing material 72 may be laid inside the shielding box 71 , and configured to absorb electromagnetic waves emitted to the internal walls of the shielding box 71 , so as to reduce reflections inside the shielding box 71 .
- the shielding box 71 and the wave-absorbing material 72 inside the shielding box 71 may constitute the anechoic chamber 70 .
- the controller 50 and the power detection device 60 may be arranged in a same housing, and the housing is located outside the anechoic chamber 70 .
- the system for testing a wireless terminal may further include a clamp (not illustrated in figures).
- the clamp is configured to fix the device under test and adjust an angle of the device under test according to the test demand.
- the absorb screen 40 is made of wave-absorbing material, and the wave-absorbing material may be a sponge dipped by carbon powder.
- the device under test 10 , the test antenna 20 , the reflecting surface 30 and the absorbing screen 40 are arranged at corresponding positions by a support part made of a nonmetallic material.
- the support part may be made of a nonmetallic material with a low dielectric constant, such as rigid foams.
- the device under test 10 and the test antenna 20 are supported and fixed on the two foci of the ellipsoid, and the reflecting surface 30 and the absorb screen 40 are arranged in corresponding positions.
- angles which correspond to biggest radiation intensity of the device under test are usually selected to be measured to save time.
- the number and position(s) of the reflecting surface(s), the shape of the reflecting surface and other parameters may be set according to the test demand.
- the three reflecting surfaces are located around one focus, a plane containing the focus and perpendicular to the long axis of the ellipsoid is intersected with the three reflecting surfaces, and the three reflecting surfaces are not opposite to each other.
- the other three reflecting surfaces are in a plane perpendicular to the long axis of the ellipsoid, and closer to the other focus.
- the reflecting surface may also be in an annular shape as illustrated in FIG. 8 or in shape of partial of the ellipsoidal surface as illustrated in FIG. 9 .
- a manufacture cost may be reduced and the distance between the device under test and the test antenna may be smaller, such that the test system has a smaller volume, a lower cost, and be more suitable for manufacture.
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Aerials With Secondary Devices (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
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CN201510169661.1A CN106161704B (zh) | 2015-04-10 | 2015-04-10 | 无线终端的测试系统 |
CN201510169661 | 2015-04-10 | ||
CN201510169661.1 | 2015-04-10 | ||
PCT/CN2016/077237 WO2016161898A1 (zh) | 2015-04-10 | 2016-03-24 | 无线终端的测试系统 |
Publications (2)
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US20180080968A1 US20180080968A1 (en) | 2018-03-22 |
US9964577B2 true US9964577B2 (en) | 2018-05-08 |
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US15/565,305 Active US9964577B2 (en) | 2015-04-10 | 2016-03-24 | Wireless terminal testing system |
Country Status (4)
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US (1) | US9964577B2 (zh) |
EP (1) | EP3282267A4 (zh) |
CN (1) | CN106161704B (zh) |
WO (1) | WO2016161898A1 (zh) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180172747A1 (en) * | 2015-04-10 | 2018-06-21 | General Test Systems Inc. | System for testing wireless terminal and method for controlling the same |
US10177863B1 (en) * | 2017-10-02 | 2019-01-08 | Rohde & Schwarz Gmbh & Co. Kg | Test system and method for over the air (OTA) measurements with a dynamic adjustable grid |
US10393786B2 (en) | 2017-12-15 | 2019-08-27 | Rohde & Schwarz Gmbh & Co. Kg | Test system and method for over the air (OTA) measurements based on randomly adjusted measurement points |
US20190288748A1 (en) * | 2018-03-14 | 2019-09-19 | Rohde & Schwarz Gmbh & Co. Kg | Measurement system and method for operating a measurement system |
US10903916B1 (en) * | 2019-07-01 | 2021-01-26 | Rohde & Schwarz Gmbh & Co. Kg | Measurement system and corresponding method for investigating the receive behavior of a device under test |
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SE540655C2 (en) * | 2017-03-06 | 2018-10-09 | Bluetest Ab | Arrangement and method for measuring the performance of devices with wireless capability |
US10333632B2 (en) * | 2017-04-03 | 2019-06-25 | Ets-Lindgren, Inc. | Method and system for testing beam forming capabilities of wireless devices |
JP6824204B2 (ja) * | 2018-02-05 | 2021-02-03 | アンリツ株式会社 | 無線端末測定装置 |
CN109342834B (zh) * | 2018-09-29 | 2020-10-16 | 北京小米移动软件有限公司 | 一种终端天线的测试装置 |
CN111211846B (zh) * | 2018-11-22 | 2022-05-17 | 深圳市通用测试系统有限公司 | 无线终端的测试系统 |
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CN111864361B (zh) * | 2019-04-29 | 2023-03-28 | 深圳市通用测试系统有限公司 | 天线单元及具有其的双极化天线 |
CN110557212A (zh) * | 2019-07-15 | 2019-12-10 | 上海无线通信研究中心 | 基于扩展紧缩场测试的毫米波终端测试系统及其方法 |
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CN113125863B (zh) * | 2021-04-22 | 2022-05-13 | 中国人民解放军国防科技大学 | 限幅天线测试系统和方法 |
CN115825592B (zh) * | 2023-02-23 | 2023-04-21 | 广东省计量科学研究院(华南国家计量测试中心) | 基于量子传感的电场精密测量新型分布式系统 |
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US10416214B2 (en) * | 2015-04-10 | 2019-09-17 | General Test Systems Inc. | System for testing wireless terminal and method for controlling the same |
US10177863B1 (en) * | 2017-10-02 | 2019-01-08 | Rohde & Schwarz Gmbh & Co. Kg | Test system and method for over the air (OTA) measurements with a dynamic adjustable grid |
US10393786B2 (en) | 2017-12-15 | 2019-08-27 | Rohde & Schwarz Gmbh & Co. Kg | Test system and method for over the air (OTA) measurements based on randomly adjusted measurement points |
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Also Published As
Publication number | Publication date |
---|---|
CN106161704A (zh) | 2016-11-23 |
US20180080968A1 (en) | 2018-03-22 |
EP3282267A4 (en) | 2019-01-02 |
WO2016161898A1 (zh) | 2016-10-13 |
EP3282267A1 (en) | 2018-02-14 |
CN106161704B (zh) | 2019-07-12 |
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